esc Ram 2500 2020 Service Manual

250STARTING AND OPERATING
Transfer Case Position Indicator Light
The “Transfer Case Position Indicator Light” in
the instrument cluster is used to alert the driver
that the front axle is fully engaged and all four
wheels are driving.
AIR SUSPENSION SYSTEM — IF EQUIPPED
Description
This air suspension system is a rear leveling ride
height system. The main purpose of this system
is to maintain the truck’s rear ride height level.
There are two selectable heights that can be
chosen based on your operating conditions.
The system requires that the ignition be in the
ON/RUN position or the engine running with
zero vehicle speed for all user requested
changes and load leveling.
Rear Leveling Ride Height Switch

Normal Ride Height (NRH) – This is the standard
position of the suspension and is meant for
normal driving. It will automatically adjust to
maintain the rear ride height as conditions
change.
Alternate Trailer Height (ATH) – Lowers the
vehicle approximately 1 inch (25 mm) for a level
truck, to be used as required while trailer
towing. It will automatically adjust to maintain
the rear ride height as conditions change.
Trailer Decoupling/Unloading - The air suspen-
sion system will continue to load level after the
vehicle has been turned off for 10 minutes
without compressor activation. This allows for
easy removal of a trailer and/or load from the
back of the truck by maintaining the ride height.
After 10 minutes you will need to turn the igni -tion to the run position for the air suspension to
re-level due to addition/removal of load in the
vehicle. If the air suspension system is disabled
using the settings menu (Tire Jack Mode, Trans
-
port Mode, Alignment Mode, or Bed Lowering
Mode) the system will remain disabled when
the vehicle is turned off. Reactivating the air
suspension can be accomplished via the
settings menu or driving the vehicle above
5 mph (8 km/h) for Tire Jack Mode, Alignment
Mode, Transport Mode and Bed Lowering
Mode.
NOTE:
Most 3500 models will not lower to Alternate
Trailer Height (ATH) when unloaded.
Refer to “Trailer Towing” in “Starting And
Operating” for further information.
WARNING!
The air suspension system uses a high
pressure volume of air to operate the system.
To avoid personal injury or damage to the
system, see your authorized dealer for
service.

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STARTING AND OPERATING259
slowly proceed over the top. If the wheels
start to slip as you approach the crest of a
hill, ease off the accelerator and maintain
headway by turning the steering wheel no
more than a quarter turn quickly back and
forth. This will provide a fresh "bite" into the
surface and will usually provide enough trac -
tion to complete the climb. If you do not make
it to the top, place the vehicle in REVERSE
and back straight down the grade using
engine resistance along with the vehicle
brakes.
Driving Downhill – Before driving down a
steep hill you need to determine if it is too
steep for a safe descent. What is the surface
traction? Is the grade too steep to maintain a
slow controlled descent? Are there obsta -
cles? Is it a straight descent? Is there plenty
of distance at the base of the hill to regain
control if the vehicle descends too fast? If
you feel confident in your ability to proceed then make sure you are in 4WD LOW with the
transmission in FIRST gear (manually select
FIRST gear on automatic transmissions) and
proceed with caution. Allow engine braking to
control the descent and apply your brakes if
necessary, but do not allow the tires to lock.
Driving Across An Incline
– If at all possible
avoid driving across an incline. If it is neces -
sary, know your vehicle's abilities. Driving
across an incline places more weight on the
downhill wheels, which increases the possi -
bilities of a downhill slide or rollover. Make
sure the surface has good traction with firm
and stable soils. If possible transverse the
incline at an angle heading slightly up or
down.
If You Stall Or Begin To Lose Headway – If you
stall or begin to lose headway while climbing
a steep hill, allow your vehicle to come to a
stop and immediately apply the brake.
Restart the engine and shift into REVERSE.
Back slowly down the hill allowing the
compression braking of the engine and trans -
mission to help regulate your speed. If the
brakes are required to control vehicle speed,
apply them lightly and avoid locking or skid-
ding the tires.
WARNING!
Never attempt to climb a hill at an angle or
turn around on a steep grade. Driving across
an incline increases the risk of a roll over,
which may result in severe injury or death.
WARNING!
Do not descend a steep grade in NEUTRAL.
Use vehicle brakes in conjunction with engine
braking. Descending a grade too fast could
cause you to lose control and be seriously
injured or killed.
WARNING!
Driving across an incline increases the risk of
a rollover, which may result in severe injury.
WARNING!
If the engine stalls or you lose headway or
cannot make it to the top of a steep hill or
grade, never attempt to turn around. To do so
may result in tipping and rolling the vehicle,
which may result in severe injury. Always back
carefully straight down a hill in REVERSE.
Never back down a hill in NEUTRAL using only
the vehicle brakes. Never drive diagonally
across a hill, always drive straight up or down.
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278STARTING AND OPERATING
When the brakes are overheated.
When the driver door is open at low speed.
When the driver seat belt is unbuckled at low
speed.
Electronic Stability Control (ESC) Full Off
mode is active.
To Activate/Deactivate
Push and release the Adaptive Cruise Control
(ACC) on/off button. The ACC menu in the
instrument cluster displays “ACC Ready.”

Adaptive Cruise Control Ready

To turn the system off, push and release the
Adaptive Cruise Control (ACC) on/off button
again. At this time, the system will turn off and the instrument cluster display will show “Adap
-
tive Cruise Control (ACC) Off.”

Adaptive Cruise Control Off

To Set A Desired ACC Speed
When the vehicle reaches the speed desired,
push the SET (-) button and release. The instru -
ment cluster display will show the set speed.
If the system is set when the vehicle speed is
below 20 mph (32 km/h), the set speed shall
be defaulted to 20 mph (32 km/h). If the
system is set when the vehicle speed is above
20 mph (32 km/h), the set speed shall be the
current speed of the vehicle.
NOTE:
ACC cannot be set if there is a stationary vehicle
in front of your vehicle in close proximity.
Remove your foot from the accelerator pedal
after the ACC has been set. If you do not, the
vehicle may continue to accelerate beyond the
set speed. If this occurs:
The message “ACC DRIVER OVERRIDE” will
display in the instrument cluster display.
The system will not be controlling the
distance between your vehicle and the
vehicle ahead. The vehicle speed will only be
determined by the position of the accelerator
pedal.
WARNING!
Leaving the Adaptive Cruise Control (ACC)
system on when not in use is dangerous. You
could accidentally set the system or cause it
to go faster than you want. You could lose
control and have a collision. Always leave the
system off when you are not using it.

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STARTING AND OPERATING279
To Cancel
The following conditions cancel the system:
The brake pedal is applied.
The CANCEL button is pushed.
An Anti-Lock Brake System (ABS) event
occurs.
The gear selector is removed from the DRIVE
position.
The Electronic Stability Control/Traction
Control System (ESC/TCS) activates.
The vehicle parking brake is applied.
Driver seatbelt is unbuckled at low speeds.
Driver door is opened at low speeds.
A Trailer Sway Control (TSC) event occurs.
The driver switches ESC to Full Off mode.
The braking temperature exceeds normal
range (overheated).
The trailer brake is applied manually (if
equipped).
To Turn Off
The system will turn off and clear the set speed
in memory if:
The Adaptive Cruise Control (ACC) on/off
button is pushed.
The Normal (Fixed Speed) Cruise Control on/
off button is pushed.
The ignition is placed in the OFF position.
You switch to Four-Wheel Drive Low.
To Resume
If there is a set speed in memory push the RES
(+) button and then remove your foot from the
accelerator pedal. The instrument cluster
display will display the last set speed.
NOTE:
If your vehicle stays at standstill for longer
than two seconds, the driver will have to push
the RES (+) button to reengage the ACC to the
existing set speed.
ACC cannot be resumed if there is a
stationary vehicle in front of your vehicle in
close proximity.
To Vary The Speed Setting
To Increase Speed
While ACC is set, you can increase the set speed
by pushing the RES (+) button.
The speed increment shown is dependent on
the chosen speed unit of U.S. (mph) or Metric
(km/h):
U.S. Speed (mph)
Pushing the RES (+) button once will result in
a 1 mph increase in set speed. Each subse -
quent tap of the button results in an increase
of 1 mph.
If the button is continually pushed, the set
speed will continue to increase in 5 mph
increments until the button is released. The
WARNING!
The Resume function should only be used if
traffic and road conditions permit. Resuming
a set speed that is too high or too low for
prevailing traffic and road conditions could
cause the vehicle to accelerate or decelerate
too sharply for safe operation. Failure to
follow these warnings can result in a collision
and death or serious personal injury.
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280STARTING AND OPERATING
increase in set speed is reflected in the
instrument cluster display.
Metric Speed (km/h)
Pushing the RES (+) button once will result in
a 1 km/h increase in set speed. Each subse -
quent tap of the button results in an increase
of 1 km/h.
If the button is continually pushed, the set
speed will continue to increase in 10 km/h
increments until the button is released. The
increase in set speed is reflected in the
instrument cluster display.
To Decrease Speed
While ACC is set, the set speed can be
decreased by pushing the SET (-) button.
The speed decrement shown is dependent on
the chosen speed unit of U.S. (mph) or Metric
(km/h):
U.S. Speed (mph)
Pushing the SET (-) button once will result in
a 1 mph decrease in set speed. Each subse -
quent tap of the button results in a decrease
of 1 mph.
If the button is continually pushed, the set
speed will continue to decrease in 5 mph decrements until the button is released. The
decrease in set speed is reflected in the
instrument cluster display.
Metric Speed (km/h)
Pushing the SET (-) button once will result in
a 1 km/h decrease in set speed. Each subse -
quent tap of the button results in a decrease
of 1 km/h.
If the button is continually pushed, the set
speed will continue to decrease in 10 km/h
decrements until the button is released. The
decrease in set speed is reflected in the
instrument cluster display.
NOTE:
When you override and push the RES (+)
button or SET (-) buttons, the new set speed
will be the current speed of the vehicle.
When you use the SET (-) button to decel -
erate, if the engine’s braking power does not
slow the vehicle sufficiently to reach the set
speed, the brake system will automatically
slow the vehicle.
The ACC system decelerates the vehicle to a
full stop when following a target vehicle. If an
ACC host vehicle follows a target vehicle to a standstill, after two seconds the driver will
either have to push the RES (+) button, or
apply the accelerator pedal to reengage the
ACC to the existing set speed.
The ACC system maintains set speed when
driving uphill and downhill. However, a slight
speed change on moderate hills is normal. In
addition, downshifting may occur while
climbing uphill or descending downhill. This
is normal operation and necessary to main
-
tain set speed. When driving uphill and down -
hill, the ACC system will cancel if the braking
temperature exceeds normal range (over -
heated).
Setting The Following Distance In ACC
The specified following distance for ACC can be
set by varying the distance setting between four
bars (longest), three bars (long), two bars
(medium) and one bar (short). Using this
distance setting and the vehicle speed, ACC
calculates and sets the distance to the vehicle
ahead. This distance setting displays in the
instrument cluster display.

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STARTING AND OPERATING289
quent tap of the button results in a decrease
of 1 mph.
If the button is continually pushed, the set
speed will continue to decrease in 5 mph
decrements until the button is released. The
decrease in set speed is reflected in the
instrument cluster display.
Metric Speed (km/h)
Pushing the SET (-) button once will result in
a 1 km/h decrease in set speed. Each subse -
quent tap of the button results in a decrease
of 1 km/h.
If the button is continually pushed, the set
speed will continue to decrease in 10 km/h
decrements until the button is released. The
decrease in set speed is reflected in the
instrument cluster display.
To Cancel
The following conditions will cancel the Normal
(Fixed Speed) Cruise Control without clearing
the memory:
The brake pedal is applied.
The CANCEL button is pushed.
The Electronic Stability Control/Traction
Control System (ESC/TCS) activates.
The vehicle parking brake is applied.
The braking temperature exceeds normal
range (overheated).
The gear selector is removed from the DRIVE
position.
The driver switches ESC to Full Off mode.
To Resume Speed
To resume a previously set speed, push the RES
(+) button and release. Resume can be used at
any speed above 20 mph (32 km/h).
To Turn Off
The system will turn off and erase the set speed
in memory if:
The Normal (Fixed Speed) Cruise Control on/
off button is pushed.
The ignition is placed in the OFF position.
You engage Four-Wheel Drive Low.
The Adaptive Cruise Control (ACC) on/off
button is pushed.
PARKSENSE REAR PARK ASSIST — IF
EQUIPPED
The ParkSense Rear Park Assist system
provides visual and audible indications of the
distance between the rear fascia and a
detected obstacle when backing up (e.g. during
a parking maneuver). Refer to “ParkSense
System Usage Precautions” in this section for
limitations of this system and recommenda -
tions.
ParkSense will retain the system state (enabled
or disabled) from the previous ignition cycle
when the ignition is placed in the ON/RUN posi -
tion.
ParkSense can be active only when the gear
selector is in REVERSE. If ParkSense is enabled
at this gear selector position, the system will
remain active until the vehicle speed is
increased to approximately 7 mph (11 km/h) or
above. When in REVERSE and above the
system's operating speed, a warning will appear
within the instrument cluster display indicating
the vehicle speed is too fast. The system will
become active again if the vehicle speed is
decreased to speeds less than approximately
6 mph (9 km/h).
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STARTING AND OPERATING315
vaporized, it converts smog-forming nitrogen
oxides (NOx) into harmless nitrogen (N2) and
water vapor (H2O), two natural components of
the air we breathe. You can operate with the
comfort that your vehicle is contributing to a
cleaner, healthier world environment for this
and generations to come.
System Overview
This vehicle is equipped with a Diesel Exhaust
Fluid (DEF) injection system and a Selective
Catalytic Reduction (SCR) catalyst to meet the
emission requirements.
The DEF injection system consists of the
following components:
DEF tank
DEF pump
DEF injector
Electronically-heated DEF lines
DEF control module
NOx sensors
Temperature sensors
SCR catalyst
UQS Sensor Refer to “Instrument Cluster Display” in
“Getting To Know Your Instrument Panel” for
system messages and warnings.
NOTE:
Your vehicle is equipped with a DEF injection
system. You may occasionally hear an
audible clicking noise. This is normal opera
-
tion.
The DEF pump will run for a period of time
after engine shutdown to purge the DEF
system. This is normal operation.
Diesel Exhaust Fluid Storage
Diesel Exhaust Fluid (DEF) is considered a very
stable product with a long shelf life. If DEF is
kept in temperatures between 10°F and 90°F
(-12°C and 32°C), it will last a minimum of one
year.
DEF is subject to freezing at the lowest tempera-
tures. For example, DEF may freeze at tempera-
tures at or below 12°F (-11°C). The system has
been designed to operate in this environment. NOTE:
When working with DEF, it is important to know
that:
Any containers or parts that come into
contact with DEF must be DEF compatible
(plastic or stainless steel). Copper, brass,
aluminum, iron or non-stainless steel should
be avoided as they are subject to corrosion
by DEF.
If DEF is spilled, it should be wiped up
completely.
Adding Diesel Exhaust Fluid
The DEF gauge (located on the instrument
cluster) will display the level of DEF remaining in
the tank. Refer to “Instrument Cluster” and
“Instrument Cluster Descriptions” in “Getting To
Know Your Instrument Panel” for further infor
-
mation.
NOTE:
Driving conditions (altitude, vehicle speed,
load, etc.) will affect the amount of DEF that
is used in your vehicle.
Another factor is that outside temperature
can affect DEF consumption. In cold condi -
tions, 12°F (-11°C) and below, the DEF
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STARTING AND OPERATING319
The recommended way to measure GTW is to
put your fully loaded trailer on a vehicle scale.
The entire weight of the trailer must be
supported by the scale.
Gross Combination Weight Rating (GCWR)
The GCWR is the total allowable weight of your
vehicle and trailer when weighed in combina -
tion.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum capacity of the front
and rear axles. Distribute the load over the front
and rear axles evenly. Make sure that you do
not exceed either front or rear GAWR. Refer to
“Vehicle Loading/Vehicle Certification Label” in
“Starting And Operating” for further informa -
tion.
Tongue Weight (TW)
The tongue weight is the downward force
exerted on the hitch ball by the trailer. You must
consider this as part of the load on your vehicle.
Trailer Frontal Area
The frontal area is the maximum height multi -
plied by the maximum width of the front of a
trailer.
Trailer Sway Control
The trailer sway control can be a mechanical
telescoping link that can be installed between
the hitch receiver and the trailer tongue that
typically provides adjustable friction associated
with the telescoping motion to dampen any
unwanted trailer swaying motions while trav -
eling. If equipped, the electronic Trailer Sway Control
(TSC) recognizes a swaying trailer and automat
-
ically applies individual wheel brakes and/or
reduces engine power to attempt to eliminate
the trailer sway.
Weight-Carrying Hitch
A weight-carrying hitch supports the trailer
tongue weight, just as if it were luggage located
at a hitch ball or some other connecting point of
the vehicle. These kinds of hitches are the most
popular on the market today and they are
commonly used to tow small and medium sized
trailers.
Weight-Distributing Hitch
A weight-distributing system works by applying
leverage through spring (load) bars. They are
typically used for heavier loads to distribute
trailer tongue weight to the tow vehicle's front
axle and the trailer axle(s). When used in accor -
dance with the manufacturer's directions, it
provides for a more level ride, offering more
consistent steering and brake control, thereby
enhancing towing safety. The addition of a fric -
tion/hydraulic sway control also dampens sway
caused by traffic and crosswinds and contrib -
utes positively to tow vehicle and trailer
stability. Trailer Sway Control (TSC) and a weight
WARNING!
If the gross trailer weight is 5,000 lbs (2,267 kg)
or more, it is recommended to use a
weight-distributing hitch to ensure stable
handling of your vehicle. If you use a standard
weight-carrying hitch, you could lose control of
your vehicle and cause a collision.
WARNING!
It is important that you do not exceed the
maximum front or rear GAWR. A dangerous
driving condition can result if either rating is
exceeded. You could lose control of the
vehicle and have a collision.
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STARTING AND OPERATING329
Speed Control — If Equipped
Do not use on hilly terrain or with heavy
loads.
When using the Speed Control, if you experi -
ence speed drops greater than 10 mph
(16 km/h), disengage until you can get back
to cruising speed.
Use Speed Control in flat terrain and with
light loads to maximize fuel efficiency.
Cooling System
To reduce potential for engine and transmission
overheating, take the following actions:
City Driving
In city traffic — while stopped, place the trans -
mission in NEUTRAL, but do not increase
engine idle speed.
Highway Driving
Reduce speed.
Temporarily turn off air conditioning.
Air Suspension System
To aid in attaching/detaching the trailer from
the vehicle, the air suspension system can be
used. Refer to “Air Suspension System” in “Starting And Operating” for further informa
-
tion.
NOTE:
The vehicle must remain in the engine running
position while attaching a trailer for proper
leveling of the air suspension system.
SNOWPLOW
Snowplow Prep Packages are available as a
factory installed option. These packages
include components necessary to equip your
vehicle with a snowplow.
NOTE:
Before installation of a snowplow it is highly
recommended that the owner/installer obtain
and follow the recommendations contained
within the current Body Builders Guide. See
your authorized dealer, installer or snowplow
manufacturer for this information. There are
unique electrical systems that must be
connected to properly ensure operator safety
and prevent overloading vehicle systems.
Before Plowing
Check the hydraulic system for leaks and
proper fluid level.
Check the mounting bolts and nuts for proper
tightness.
Check the runners and cutting edge for
excessive wear. The cutting edge should be
¼ to ½ inches (6 cm to 1.2 cm) above ground
in snow plowing position.
Check that snowplow lighting is connected
and functioning properly.
WARNING!
Attaching a snowplow to this vehicle could
adversely affect performance of the airbag
system in a collision. Do not expect that the
airbag will perform as described earlier in this
manual.
CAUTION!
The “Lamp Out” indicator could illuminate if
exterior lamps are not properly installed.
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350IN CASE OF EMERGENCY

Dual Rear Wheel Jack Placement

6. Finish tightening the lug nuts. Push down on the lug wrench while at the end of the handle
for increased leverage. Tighten the lug nuts in
a star pattern until each nut has been tight -
ened twice. For the correct lug nut torque refer
to “Wheel And Tire Torque Specifications” in
“Technical Specifications”. If in doubt about
the correct tightness, have them checked with
a torque wrench by an authorized dealer or
service station. 7. Install the wheel center cap and remove the
wheel blocks. Do not install chrome or
aluminum wheel center caps on the spare
wheel. This may result in cap damage.
8. Lower the jack to its fully closed position. Stow the replaced tire, jack, and tools as
previously described.
NOTE:
The bottle jack will not lower by turning the dial
(thumbwheel) by hand, it may be necessary to
use the jack driver in order to lower the jack.
9. Adjust the tire pressure when possible.
NOTE:
Do not oil wheel studs. For chrome wheels, do
not substitute with chrome plated lug nuts.
To Stow The Flat Or Spare
NOTE:
Have the flat tire repaired or replaced immedi -
ately.

1. Turn the wheel so that the valve stem is facing the ground and toward the rear of
the vehicle for convenience in checking the
spare tire inflation. Slide the wheel retainer
through the center of the wheel.

Reinstalling The Retainer

WARNING!
A loose tire or jack thrown forward in a
collision or hard stop, could endanger the
occupants of the vehicle. Always stow the jack
parts and the spare tire in the places
provided.
WARNING!
A loose tire or jack thrown forward in a
collision or hard stop could endanger the
occupants of the vehicle. Always stow the jack
parts and the spare tire in the places
provided. Have the deflated (flat) tire repaired
or replaced immediately.

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